This commit adds support for the following items in psql, able to show a
service name, when available:
- Variable SERVICE.
- Substitution %s in PROMPT{1,2,3}.
This relies on 4b99fed754, that has made the service name available in
PGconn for libpq.
Author: Michael Banck
Reviewed-by: Greg Sabino Mullane
Discussion: https://postgr.es/m/6723c612.050a0220.1567f4.b94a@mx.google.com
This commit adds one field to PGconn for the database service name (if
any), with PQservice() as routine to retrieve it. Like the other
routines of this area, NULL is returned as result if the connection is
NULL.
A follow-up patch will make use of this feature to be able to display
the service name in the psql prompt.
Author: Michael Banck
Reviewed-by: Greg Sabino Mullane
Discusion: https://postgr.es/m/6723c612.050a0220.1567f4.b94a@mx.google.com
0f5738202 adjusted the execGrouping.c code so it made use of ExprStates to
generate hash values. That commit made a wrong assumption that the slot
type to pass to ExecBuildHash32FromAttrs() is always &TTSOpsMinimalTuple.
That's not the case as the slot type depends on the slot type passed to
LookupTupleHashEntry(), which for nodeRecursiveunion.c, could be any of
the current slot types.
Here we fix this by adding a new parameter to BuildTupleHashTableExt()
to allow the slot type to be passed in. In the case of nodeSubplan.c
and nodeAgg.c the slot type is always &TTSOpsVirtual, so for both of
those cases, it's beneficial to pass the known slot type as that allows
ExecBuildHash32FromAttrs() to skip adding the tuple deform step to the
resulting ExprState. Another possible fix would have been to have
ExecBuildHash32FromAttrs() set "fetch.kind" to NULL so that
ExecComputeSlotInfo() always determines the EEOP_INNER_FETCHSOME is
required, however, that option isn't favorable as slows down aggregation
and hashed subplan evaluation due to the extra (needless) deform step.
Thanks to Nathan Bossart for bisecting to find the offending commit
based on Paul's report.
Reported-by: Paul Ramsey <pramsey@cleverelephant.ca>
Discussion: https://postgr.es/m/99F064C1-B3EB-4BE7-97D2-D2A0AA487A71@cleverelephant.ca
If a dshash table grows very large (e.g., the dshash table for
cumulative statistics when there are millions of tables), resizing
it may fail with an error like:
ERROR: invalid DSA memory alloc request size 1073741824
To fix, permit dshash resizing to allocate more than 1 GB by
providing the DSA_ALLOC_HUGE flag.
Reported-by: Andreas Scherbaum
Author: Matthias van de Meent
Reviewed-by: Cédric Villemain, Michael Paquier, Andres Freund
Discussion: https://postgr.es/m/80a12d59-0d5e-4c54-866c-e69cd6536471%40pgug.de
Backpatch-through: 13
There's no need for set_simple_column_names() to compute unique
column names for join RTEs, because a finished plan tree will
not contain any join alias Vars that we could need names for.
Its other, internal callers will not pass it any join RTEs
anyway, so the upshot is we can just skip join RTEs here.
Aside from getting rid of a klugy against-its-documentation use of
set_relation_column_names, this can speed up EXPLAIN substantially
when considering many-join queries, because the upper join RTEs
tend to have a lot of columns.
Sami Imseih, with cosmetic changes by me
Discussion: https://postgr.es/m/CAA5RZ0th3q-0p1pri58z9grG8r8azmEBa8o1rtkwhLmJg_cH+g@mail.gmail.com
Rename frozen_pages to new_frozen_tuple_pages in LVRelState, the struct
used for tracking state during vacuuming of a heap relation.
frozen_pages sounds like it tracks pages set all-frozen. That is a
misnomer. It only includes pages with at least one newly frozen tuple.
It also includes pages that are not all-frozen.
Author: Melanie Plageman
Reviewed-by: Andres Freund, Masahiko Sawada, Nitin Jadhav, Bilal Yavuz
Discussion: https://postgr.es/m/ctdjzroezaxmiyah3gwbwm67defsrwj2b5fpfs4ku6msfpxeia%40mwjyqlhwr2wu
Formerly we skipped this in bootstrap/check mode and in single-user
mode. That's bad in check mode because it may allow accepting a
value of max_connections that doesn't actually work: on platforms
where semaphores consume file descriptors, there may not be enough
free FDs left over to satisfy fd.c, causing postmaster start to
fail. It's also not great in single-user mode, because fd.c will
operate with just the minimum allowable value of max_safe_fds,
resulting in excess file open/close overhead if anything moderately
complicated is done in single-user mode. (There may be some penalty
for bootstrap mode too, though probably not much.)
Discussion: https://postgr.es/m/2081982.1734393311@sss.pgh.pa.us
Previously we did this in PostmasterMain() and InitPostmasterChild(),
which meant that stack depth checking was disabled in non-postmaster
server processes, for instance in single-user mode. That seems like
a fairly bad idea, since there's no a-priori restriction on the
complexity of queries we will run in single-user mode. Moreover, this
led to not having quite the same stack depth limit in all processes,
which likely has no real-world effect but it offends my inner neatnik.
Setting the depth in main() guarantees that check_stack_depth() is
armed and has a consistent interpretation of stack depth in all forms
of server processes.
While at it, move the code associated with checking the stack depth
out of tcop/postgres.c (which was never a great home for it) into
a new file src/backend/utils/misc/stack_depth.c.
Discussion: https://postgr.es/m/2081982.1734393311@sss.pgh.pa.us
Commit dae761a87e modified brin_page_items() to return the new "empty"
flag for each BRIN range. But the new output parameter was added in the
middle, which may cause crashes when using the new binary with old
function definition.
The ideal solution would be to introduce API versioning similar to what
pg_stat_statements does, but it's too late for that as PG17 was already
released (so we can't introduce a new extension version). We could do
something similar in brin_page_items() by checking the number of output
columns (and ignoring the new flag), but it doesn't seem very nice.
Instead, simply error out and suggest updating the extension to the
latest version. pageinspect is a superuser-only extension, and there's
not much reason to run an older version. Moreover, there's a precedent
for this approach in 691e8b2e18.
Reported by Ľuboslav Špilák, investigation and patch by me. Backpatch to
17, same as dae761a87e.
Reported-by: Ľuboslav Špilák
Reviewed-by: Michael Paquier, Hayato Kuroda, Peter Geoghegan
Backpatch-through: 17
Discussion: https://postgr.es/m/VI1PR02MB63331C3D90E2104FD12399D38A5D2@VI1PR02MB6333.eurprd02.prod.outlook.com
Discussion: https://postgr.es/m/flat/3385a58f-5484-49d0-b790-9a198a0bf236@vondra.me
Commit b437571714 allowed parallel builds for BRIN, but left behind
two comments claiming only btree indexes support parallel builds.
Reported by Egor Rogov, along with similar issues in SGML docs.
Backpatch to 17, where parallel builds for BRIN were introduced.
Reported-by: Egor Rogov
Backpatch-through: 17
Discussion: https://postgr.es/m/114e2d5d-125e-07d8-94aa-5ad175fb7443@postgrespro.ru
lowerstr() and lowerstr_with_len() in ts_locale.c do the same thing as
str_tolower() that the rest of the system uses, except that the former
don't use the common locale provider framework but instead use the
global libc locale settings.
This patch replaces uses of lowerstr*() with str_tolower(...,
DEFAULT_COLLATION_OID). For instances that use a libc locale
globally, this will result in exactly the same behavior. For
instances that use other locale providers, you now get consistent
behavior and are no longer dependent on the libc locale settings (for
this case; there are others).
Most uses of these functions are for processing dictionary and
configuration files. In those cases, using the default collation
seems appropriate. At least we don't have a more specific collation
available. But the code in contrib/pg_trgm should really depend on
the collation of the columns being processed. This is not done here,
this can be done in a separate patch.
(You can probably construct some edge cases where this change would
create some locale-related upgrade incompatibility, for example if
before you used a combination of ICU and a differently-behaving libc
locale. We can document this in the release notes, but I don't think
there is anything more we can do about this.)
Reviewed-by: Jeff Davis <pgsql@j-davis.com>
Discussion: https://www.postgresql.org/message-id/flat/653f3b84-fc87-45a7-9a0c-bfb4fcab3e7d%40eisentraut.org
These do the same thing as the standard isdigit(), isspace(), and
isprint() but with multibyte and encoding support. But all the
callers are only interested in analyzing single-byte ASCII characters.
So this extra layer is overkill and we can replace the uses with the
standard functions.
All the t_is*() functions in ts_locale.c are under scrutiny because
they don't use the common locale provider framework but instead use
the global libc locale settings. For the functions being touched by
this patch, we don't need all that anyway, as mentioned above, so the
simplest solution is to just remove them. The few remaining t_is*()
functions will need a different treatment in a separate patch.
pg_trgm has some compile-time options with macros such as
KEEPONLYALNUM. These are not documented, and the non-default variant
is not supported by any test cases. As part of this undertaking, I'm
removing the non-default variant, as it is in the way of cleanup. So
in this case, the not-KEEPONLYALNUM code path is gone.
Reviewed-by: Jeff Davis <pgsql@j-davis.com>
Discussion: https://www.postgresql.org/message-id/flat/653f3b84-fc87-45a7-9a0c-bfb4fcab3e7d%40eisentraut.org
When pulling up a subquery that is under an outer join, if the
subquery's target list contains a strict expression that uses a
subquery variable, it's okay to pull up the expression without
wrapping it in a PlaceHolderVar: if the subquery variable is forced to
NULL by the outer join, the expression result will come out as NULL
too.
If the strict expression does not contain any subquery variables, the
current code always wraps it in a PlaceHolderVar. While this is not
incorrect, the analysis could be tighter: if the strict expression
contains any variables of rels that are under the same lowest nulling
outer join as the subquery, we can also avoid wrapping it. This is
safe because if the subquery variable is forced to NULL by the outer
join, the variables of rels that are under the same lowest nulling
outer join will also be forced to NULL, resulting in the expression
evaluating to NULL as well. Therefore, it's not necessary to force
the expression to be evaluated below the outer join. It could be
beneficial to get rid of such PHVs because they could imply lateral
dependencies, which force us to resort to nestloop joins.
This patch checks if the lateral references in the strict expression
contain any variables of rels under the same lowest nulling outer join
as the subquery, and avoids wrapping the expression in that case.
This is fundamentally a generalization of the optimizations for bare
Vars and PHVs introduced in commit f64ec81a8.
No backpatch as this could result in plan changes.
Author: Richard Guo
Discussion: https://postgr.es/m/CAMbWs4_ENtfRdLaM_bXAxiKRYO7DmwDBDG4_2=VTDi0mJP-jAw@mail.gmail.com
The following commands gain some information about the error position in
the query, should they fail when looking at the type used:
- CREATE TYPE (LIKE)
- CREATE TABLE OF
Both are related to typenameType() where the type name lookup is done.
These calls gain the ParseState that already exists in these paths.
Author: Kirill Reshke, Jian He
Reviewed-by: Álvaro Herrera, Michael Paquier
Discussion: https://postgr.es/m/CALdSSPhqfvKbDwqJaY=yEePi_aq61GmMpW88i6ZH7CMG_2Z4Cg@mail.gmail.com
The test was creating both the dumps to compare from the same database
on the same node, so it would never detect any mismatches when comparing
the logical dumps of the two servers.
Fixing this issue has revealed that there is a difference in the dumps:
the tablespaces paths are different. This commit uses compare_text()
with a custom comparison function to erase the difference (slightly
tweaked to be able to work with WIN32 and non-WIN32 paths). This way,
the non-relevant parts of the tablespace path are ignored from the check
with the basic structure of the query string still compared.
Author: Dagfinn Ilmari Mannsåker
Discussion: https://postgr.es/m/87h67653ns.fsf@wibble.ilmari.org
Backpatch-through: 17
Two places in the documentation suggest B-tree is the only index access
method allowing parallel builds. Commit b4375717 added parallel builds
for BRIN too, but failed to update the docs. So fix that, and backpatch
to 17, where parallel BRIN builds were introduced.
Author: Egor Rogov
Backpatch-through: 17
Discussion: https://postgr.es/m/114e2d5d-125e-07d8-94aa-5ad175fb7443@postgrespro.ru
Create API entry points pg_strlower(), etc., that work with any
provider and give the caller control over the destination
buffer. Then, move provider-specific logic into pg_locale_builtin.c,
pg_locale_icu.c, and pg_locale_libc.c as appropriate.
Discussion: https://postgr.es/m/7aa46d77b377428058403723440862d12a8a129a.camel@j-davis.com
Updates table completion for ALTER TYPE to offer CASCADE/RESTRICT for a
number of actions on attributes:
ALTER TYPE ... ADD/DROP/RENAME ATTRIBUTE ... [CASCADE|RESTRICT]
ALTER TYPE ... TYPE ... [CASCADE|RESTRICT]
Author: Kirill Reshke
Reviewed-By: Karina Litskevich
Discussion: https://postgr.es/m/CALdSSPhVELkvutquqrDB=Ujfq_Pjz=6jn-kzh+291KPNViLTfw@mail.gmail.com
The test failed if you ran the regression tests with TEMP_CONFIG with
recovery_min_apply_delay = '500ms'. Fix the race condition by waiting
for transaction to be applied in the replica, like in a few other
tests.
The failing test was introduced in commit cbfbda7841. Backpatch to all
supported versions like that commit (except v12, which is no longer
supported).
Reported-by: Alexander Lakhin
Discussion: https://www.postgresql.org/message-id/09e2a70a-a6c2-4b5c-aeae-040a7449c9f2@gmail.com
This is simply done by pushing down the ParseState available in
ProcessUtility() to DefineDomain(), giving more information about the
position of an error when running a CREATE DOMAIN query.
Most of the queries impacted by this change have been added previously
in 0172b4c944.
Author: Kirill Reshke, Jian He
Reviewed-by: Álvaro Herrera, Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/CALdSSPhqfvKbDwqJaY=yEePi_aq61GmMpW88i6ZH7CMG_2Z4Cg@mail.gmail.com
This adds a couple of tests to trigger encoding conversion when input
and server encodings do not match in COPY FROM/TO, or need_transcoding
set to true in the COPY state data. These tests rely on UTF8 <-> LATIN1
for the valid cases as LATIN1 accepts any bytes, and UTF8 <-> EUC_JP for
some of the invalid cases where a character cannot be understood,
causing a conversion failure.
Both ENCODING and client_encoding are covered. Test suggested by Andres
Freund.
Author: Sutou Kouhei
Discussion: https://postgr.es/m/20240206222445.hzq22pb2nye7rm67@awork3.anarazel.de
I went through the buildfarm's reports of "warning: variable 'foo'
might be clobbered by 'longjmp' or 'vfork' [-Wclobbered]". As usual,
none of them are live problems according to my understanding of the
effects of setjmp/longjmp, to wit that local variables might revert
to their values as of PG_TRY entry, due to being kept in registers.
But I did happen to notice that XmlTableGetValue's "cstr" variable
doesn't need to be declared outside the PG_TRY block at all (thus
giving further proof that the -Wclobbered warning has little
connection to real problems). We might as well move it inside,
and "cur" too, in hopes of eliminating one of the bogus warnings.
An \if command appearing within a false (not-to-be-executed) \if
branch was incorrectly treated the same as \elif. This could allow
statements within the inner \if to be executed when they should
not be. Also the missing inner \if stack entry would result in an
assertion failure (in assert-enabled builds) when the final \endif
is reached.
Report and patch by Michail Nikolaev. Back-patch to all
supported branches.
Discussion: https://postgr.es/m/CANtu0oiA1ke=SP6tauhNqkUdv5QFsJtS1p=aOOf_iU+EhyKkjQ@mail.gmail.com
The documentation in wal.sgml explains that old WAL files cannot be
removed or recycled until they are archived (when WAL archiving is used)
or replicated (when using replication slots). However, it did not mention
that, similarly, old WAL files are also kept until they are summarized
if WAL summarization is enabled. This commit adds that clarification
to the documentation.
Back-patch to v17 where WAL summarization was added.
Author: Fujii Masao
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/fd0eb0a5-f43b-4e06-b450-cbca011b6cff@oss.nttdata.com
The @extschema:name@ feature added by 72a5b1fc8 allows us to
make earthdistance's references to the cube extension fully
search-path-secure, so long as all those references are
resolved at extension installation time not runtime.
To do that, we must convert earthdistance's SQL functions to
the new SQL-standard style; but we wanted to do that anyway.
The functions can be updated in our customary style by running
CREATE OR REPLACE FUNCTION in an extension update script.
However, there's still problems in the "CREATE DOMAIN earth"
command: its references to cube functions could be captured
by hostile objects in earthdistance's installation schema,
if that's not where the cube extension is. Worse, the reference
to the cube type itself as the domain's base could be captured,
and that's not something we could fix after-the-fact in the
update script.
What I've done about that is to change the "CREATE DOMAIN earth"
command in the base script earthdistance--1.1.sql. Ordinarily,
changing a released extension script is forbidden; but I think
it's okay here since the results of successful (non-trojaned)
script execution will be identical to before.
A good deal of care is still needed to make the extension's scripts
proof against search-path-based attacks. We have to make sure that
all the function and operator invocations have exact argument-type
matches, to forestall attacks based on supplying a better match.
Fortunately earthdistance isn't very big, so I've just gone through
it and inspected each call to be sure of that. The only actual code
changes needed were to spell all floating-point constants in the style
'-1'::float8, rather than depending on runtime type conversions and/or
negations. (I'm not sure that the shortcuts previously used were
attackable, but removing run-time effort is a good thing anyway.)
I believe that this fixes earthdistance enough that we could
mark it trusted and remove the warnings about it that were
added by 7eeb1d986; but I've not done that here.
The primary reason for dealing with this now is that we've
received reports of pg_upgrade failing for databases that use
earthdistance functions in contexts like generated columns.
That's a consequence of 2af07e2f7 having restricted the search_path
used while evaluating such expressions. The only way to fix that
is to make the earthdistance functions independent of run-time
search_path. This patch is very much nicer than the alternative of
attaching "SET search_path" clauses to earthdistance's functions:
it is more secure and doesn't create a run-time penalty. Therefore,
I've chosen to back-patch this to v16 where @extschema:name@
was added. It won't help unless users update to 16.7 and issue
"ALTER EXTENSION earthdistance UPDATE" before upgrading to 17,
but at least there's now a way to deal with the problem without
manual intervention in the dump/restore process.
Tom Lane and Ronan Dunklau
Discussion: https://postgr.es/m/3316564.aeNJFYEL58@aivenlaptop
Discussion: https://postgr.es/m/6a6439f1-8039-44e2-8fb9-59028f7f2014@mailbox.org
POSIX says that the global variable environ shouldn't be declared in a
header, and that you have to declare it yourself. MinGW declares it in
<stdlib.h> with some macrology that messes up our declarations. Visual
Studio doesn't warn (there are clues that it may also declare it, but if
so, apparently compatibly). Suppress our declarations, on MinGW only.
This clears the last warnings on CI's optional MinGW task, and hopefully
on build farm animal fairywren too.
Like 1319997d, no back-patch for now as it's not known to be breaking
anything, and my humble goal is just to keep the MinGW build clean going
forward.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> (earlier version)
Discussion: https://postgr.es/m/CA%2BhUKGJLMh%2B6W5E4M_jSFb43gnrA_-Q6-%2BBf3HkBXyGfRFcBsQ%40mail.gmail.com
Commits 7bb3102c and 3eb77eba removed the only user of the
EXTENSION_DONT_CHECK_SIZE flag, which had previously been required to
checkpoint truncated relations. Since 7bb3102c, segments have been
opened directly for synchronization without calling _mdfd_getseg(), so
it doesn't need a mode that tolerates non-final short segments. Remove
the redundant flag and associated comments.
Reported-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/nyj4k7yur5t27rtygvx2i2lrlp6rqfvvhoiiwx4fznynksf2et%404hj2sp42alpe
If an owned sequence is considered interesting, force its owning
table to be marked interesting too. This ensures, in particular,
that we'll fetch the owning table's column names so we have the
data needed for ALTER TABLE ... ADD GENERATED. Previously there were
edge cases where pg_dump could get SIGSEGV due to not having filled in
the column names. (The known case is where the owning table has been
made part of an extension while its identity sequence is not a member;
but there may be others.)
Also, if it's an identity sequence, force its dumped-components mask
to exactly match the owning table: dump definition only if we're
dumping the table's definition, dump data only if we're dumping the
table's data, etc. This generalizes the code introduced in commit
b965f2617 that set the sequence's dump mask to NONE if the owning
table's mask is NONE. That's insufficient to prevent failures,
because for example the table's mask might only request dumping ACLs,
which would lead us to still emit ALTER TABLE ADD GENERATED even
though we didn't create the table. It seems better to treat an
identity sequence as though it were an inseparable aspect of the
table, matching the treatment used in the backend's dependency logic.
Perhaps this policy needs additional refinement, but let's wait to
see some field use-cases before changing it further.
While here, add a comment in pg_dump.h warning against writing tests
like "if (dobj->dump == DUMP_COMPONENT_NONE)", which was a bug in this
case. There is one other example in getPublicationNamespaces, which
if it's not a bug is at least remarkably unclear and under-documented.
Changing that requires a separate discussion, however.
Per report from Artur Zakirov. Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAKNkYnwXFBf136=u9UqUxFUVagevLQJ=zGd5BsLhCsatDvQsKQ@mail.gmail.com
With not-null constraints defined in child tables for columns that are
coming from their parent tables, we were printing ALTER TABLE SET NOT
NULL commands that were missing the constraint name, so the original
constraint name was being lost, which is bogus. Fix by instead adding
a table-constraint constraint declaration with the correct constraint
name in the CREATE TABLE instead.
Oversight in commit 14e87ffa5c.
We could have fixed it by changing the ALTER TABLE SET NOT NULL to ALTER
TABLE ADD CONSTRAINT, but I'm not sure that's any better. A potential
problem here might be that if sent to a non-Postgres server, the new
pg_dump output would fail because the "CONSTRAINT foo NOT NULL colname"
syntax isn't SQL-conforming. However, Postgres' implementation of
inheritance is already non-SQL-conforming, so that'd likely fail anyway.
This problem was only noticed by Ashutosh's proposed test framework for
pg_dump, https://postgr.es/m/CAExHW5uF5V=Cjecx3_Z=7xfh4rg2Wf61PT+hfquzjBqouRzQJQ@mail.gmail.com
Author: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reported-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/CAExHW5tbdgAKDfqjDJ-7Fk6PJtHg8D4zUF6FQ4H2Pq8zK38Nyw@mail.gmail.com
This reverts commit 562bee0fc1.
We received a report from the field about this change in behavior,
so it seems best to revert this commit and to add proper
multibyte-aware truncation as a follow-up exercise.
Fixes bug #18711.
Reported-by: Adam Rauch
Reviewed-by: Tom Lane, Bertrand Drouvot, Bruce Momjian, Thomas Munro
Discussion: https://postgr.es/m/18711-7503ee3e449d2c47%40postgresql.org
Backpatch-through: 17
One comment of PgStat_TableCounts mentioned that its pending stats use
memcmp() to check for the all-zero case if there is any activity. This
is not true since 07e9e28b56, as pg_memory_is_all_zeros() is used.
PgStat_FunctionCounts incorrectly documented that it relied on memcpy().
This has never been correct, and not relevant because function
statistics do not have an all-zero check for pending stats.
Checkpoint and bgwriter statistics have been always relying on memcmp()
or pg_memory_is_all_zeros() (since 07e9e28b56 for the latter), and never
mentioned the dependency on event counters for their all-zero checks.
Let's document these properties, like the table statistics.
Author: Bertrand Drouvot
Discussion: https://postgr.es/m/Z1hNLvcPgVLPxCoc@ip-10-97-1-34.eu-west-3.compute.internal
d4c3a156c added support that when the GROUP BY contained all of the
columns belonging to a relation's PRIMARY KEY, all other columns
belonging to that relation would be removed from the GROUP BY clause.
That's possible because all other columns are functionally dependent on
the PRIMARY KEY and those columns alone ensure the groups are distinct.
Here we expand on that optimization and allow it to work for any unique
indexes on the table rather than just the PRIMARY KEY index. This
normally requires that all columns in the index are defined with NOT NULL,
however, we can relax that requirement when the index is defined with
NULLS NOT DISTINCT.
When there are multiple suitable indexes to allow columns to be removed,
we prefer the index with the least number of columns as this allows us
to remove the highest number of GROUP BY columns. One day, we may want to
revisit that decision as it may make more sense to use the narrower set of
columns in terms of the width of the data types and stored/queried data.
This also adjusts the code to make use of RelOptInfo.indexlist rather
than looking up the catalog tables.
In passing, add another short-circuit path to allow bailing out earlier
in cases where it's certainly not possible to remove redundant GROUP BY
columns. This early exit is now cheaper to do than when this code was
originally written as 00b41463c made it cheaper to check for empty
Bitmapsets.
Patch originally by Zhang Mingli and later worked on by jian he, but after
I (David) worked on it, there was very little of the original left.
Author: Zhang Mingli, jian he, David Rowley
Reviewed-by: jian he, Andrei Lepikhov
Discussion: https://postgr.es/m/327990c8-b9b2-4b0c-bffb-462249f82de0%40Spark
In commit 5668a857d, we fixed an issue with incorrect results in right
semi joins and introduced a test case to verify the fix. The test
case involves SubPlans and InitPlans, which may not be immediately
apparent in relation to the issue we addressed.
This patch simplifies the test case with a more straightforward query.
Per discussion with Melanie Plageman.
Author: Richard Guo
Discussion: https://postgr.es/m/CAAKRu_a-Cip2XCXp13fmxq+T9BhLAVApHTyjr94awL2mbXHC-Q@mail.gmail.com
The following commands gain increased coverage for some of the errors
they can trigger:
- ALTER TABLE .. ALTER COLUMN
- CREATE DOMAIN
- CREATE TYPE (LIKE)
This has come up while discussing the possibility to add more
information about the location of the error in such queries, and it
is useful on its own as there was no coverage until now for the
patterns added in this commit.
Author: Jian He, Kirill Reshke
Reviewed-By: Álvaro Herrera, Michael Paquier
Discussion: https://postgr.es/m/CALdSSPhqfvKbDwqJaY=yEePi_aq61GmMpW88i6ZH7CMG_2Z4Cg@mail.gmail.com
Traditionally, remove_useless_groupby_columns() was called during
grouping_planner() directly after the call to preprocess_groupclause().
While in many ways, it made sense to populate the field and remove the
functionally dependent columns from processed_groupClause at the same
time, it's just that doing so had the disadvantage that
remove_useless_groupby_columns() was being called before the RelOptInfos
were populated for the relations mentioned in the query. Not having
RelOptInfos available meant we needed to manually query the catalog tables
to get the required details about the primary key constraint for the
table.
Here we move the remove_useless_groupby_columns() call to
query_planner() and put it directly after the RelOptInfos are populated.
This is fine to do as processed_groupClause still isn't final at this
point as it can still be modified inside standard_qp_callback() by
make_pathkeys_for_sortclauses_extended().
This commit is just a refactor and simply moves
remove_useless_groupby_columns() into initsplan.c. A planned follow-up
commit will adjust that function so it uses RelOptInfo instead of doing
catalog lookups and also teach it how to use unique indexes as proofs to
expand the cases where we can remove functionally dependent columns from
the GROUP BY.
Reviewed-by: Andrei Lepikhov, jian he
Discussion: https://postgr.es/m/CAApHDvqLezKwoEBBQd0dp4Y9MDkFBDbny0f3SzEeqOFoU7Z5+A@mail.gmail.com
This commit introduces the uuidv7() SQL function, which generates UUID
version 7 as specified in RFC 9652. UUIDv7 combines a Unix timestamp
in milliseconds and random bits, offering both uniqueness and
sortability.
In our implementation, the 12-bit sub-millisecond timestamp fraction
is stored immediately after the timestamp, in the space referred to as
"rand_a" in the RFC. This ensures additional monotonicity within a
millisecond. The rand_a bits also function as a counter. We select a
sub-millisecond timestamp so that it monotonically increases for
generated UUIDs within the same backend, even when the system clock
goes backward or when generating UUIDs at very high
frequency. Therefore, the monotonicity of generated UUIDs is ensured
within the same backend.
This commit also expands the uuid_extract_timestamp() function to
support UUID version 7.
Additionally, an alias uuidv4() is added for the existing
gen_random_uuid() SQL function to maintain consistency.
Bump catalog version.
Author: Andrey Borodin
Reviewed-by: Sergey Prokhorenko, Przemysław Sztoch, Nikolay Samokhvalov
Reviewed-by: Peter Eisentraut, Jelte Fennema-Nio, Aleksander Alekseev
Reviewed-by: Masahiko Sawada, Lukas Fittl, Michael Paquier, Japin Li
Reviewed-by: Marcos Pegoraro, Junwang Zhao, Stepan Neretin
Reviewed-by: Daniel Vérité
Discussion: https://postgr.es/m/CAAhFRxitJv%3DyoGnXUgeLB_O%2BM7J2BJAmb5jqAT9gZ3bij3uLDA%40mail.gmail.com
Michael Paquier